Shatterproof or safety glass is typically made of three layers: an outer glass layer, an internal synthetic resin or polymer layer which imports the shatterproof characteristics, and an inner glass layer. Although the glass is referred to as shatterproof, it readily forms conical chips when hit by a rapidly moving small object such as a pebble. The chip or break results in an air cavity in and potentially under the surface of the outer glass laminate. This initial chip can expand into a crack that extends across the glass if not promptly repaired.
The repair of chips and cracks on a piece of shatterproof glass typically is accomplished by injecting a glass repair resin into the air cavity of the damaged area. To help conceal the patch, the resin is selected to have a finished or hardened index of refraction that is close to that of the glass into which it is injected. The resin is allowed to dry and harden. Afterwards, the surface of the glass is leveled so that the surface presented is uniform across the patch. By repairing the glass, the more expensive cost of replacement is averted.
There exists many different devices and methods for repairing breaks in a windshield. U.S. Pat. No. 5,234,325 discloses an apparatus for repairing cracks along a windshield that includes positioning a cylinder over the crack in order to create a vacuum and pull air from the crack. With the vacuum in place, a side stem in communication with the cylinder allows resin to be introduced through the cylinder and into the crack. It should be noted, however, no vacuum pressure is made available for securing the apparatus to the glass. Likewise, U.S. Pat. No. 5,122,042 discloses an apparatus for repairing cracks in a windshield that includes utilizing air pressure to inject resin into a crack. The air pressure enables the resin to flow into the extended areas of the crack. Once again, no suction or vacuum is applied to the securing feet of the device.
U.S. Pat. No. 4,776,780 discloses an apparatus for repairing conical chips in a windshield that includes a diaphragm attached to the bottom of a housing. The diaphragm provides a first enclosure means in which the housing is able to attach to the windshield above the chip by means of a vacuum. Resin is introduced into the crack through a second enclosure by means of a plunger, with manipulation of the plunger alternatingly creating a vacuum and pressure in the enclosure to force the resin into the chip. The housing is removed from the glass once the resin is plunged in by rocking the housing to allow air into the first enclosure. U.S. Pat. No. 4,826,413 also discloses an apparatus for repairing chips on a windshield that includes a first vacuum cup for securing the apparatus to the windshield and a second smaller cup which is placed over the chip and through which resin is introduced. The smaller cup is in fluid connection with the larger cup such that by evacuating the larger cup, the smaller cup is simultaneously evacuated. There is no means by which the vacuum may be selectively applied to the two different components and the vacuum is produced by a mechanical pump, not manually.
Most of a windshield repair cost is attributable to labor, with supply costs being relatively low. By providing a windshield chip and crack repair kit affordably available to the average consumer, labor costs are eliminated allowing an individual to inexpensively fix a break in his or her windshield. Additionally, the system should be easy to use as well as portable, and preferably no external power source required since the locations for repair may often be remote.